The specific aim of the proposed research is to understand the way in which the W-cell population differs functionally from the X- and Y-cell populations. Electrophysiological procedures will be employed to record visual responses of isolated W-cells in the dorsal lateral geniculate nucleus. These results from W-cells will be compared to what is already known about the visual responses of X- and Y-cells. In addition, the effects of visual deprivation on W-cell development will be assessed and compared with the known visual deprivation effects on X- and Y-cell development. The objective of this research is two-fold: 1) to infer the functional significance to vision of the W, X, and Y-cell populations; and 2) to relate the physiological effects of visual deprivation to the visual deficits observed behaviorally in the deprived animals. This research will provide a better understanding of the neural deficits which underlie the impairment of vision in human amblyopia.